1. Field of the Invention
The present invention relates to an image recording and reproducing apparatus, and more particularly, to an image recording and reproducing apparatus and method, in which a current broadcasting and a previous broadcasting with respect to one image content can be viewed at the same time using multi-decoding.
2. Description of the Related Art
Automatic recording service using program information to individual's taste is based on personal television “ReplayTV” and Personal Versatile Recorder (PVR) produced by TiVo, which is one of leading companies in this field. “ReplayTV”-based service is one of so-called personal televisions. The “ReplayTV”-based service can record television broadcast programs on hard disc device (HDD) in real time, pause or rewind them while viewing programs. In addition, the service can obtain a program list, select programs considering actor or actress, theme and the like, and collect favorite programs to make one's own channel on hard disc drive.
PVR-based service is similar to a conventional video tape recorder (VTR). However, the PVR-based service can record several-hour long programs using a mass storage device (hard disc drive) instead of tape. Since programs can be recorded in real time, PVR user can view broadcasting programs except for advertisements by using the pause and rewind functions. In addition, PVR can select and record dozens kinds of programs in order to view them later.
Such a PVR system includes a tuner, a playback device and a random-accessible hard disc drive and it is an image recording and reproducing apparatus which can provide a user with a live screen stop function, a time shift function, a high speed fast forward function, and the like.
Here, the time shift function is a function that can simultaneously record and reproduce programs using disc buffer, allow the user to switch to a current broadcasting while viewing a previous broadcasting, and provide a trick play to a recorded portion.
Accordingly, the time shift function has an advantage that can freely control a reproduction of a live broadcasting stream like an existing recorded stream.
However, a reproduction of scenes in the time shift is fundamentally different from that of existing recorded contents. In other words, the reproduction of scenes in the time shift means that live scenes are continuously recorded and stored even in the time shift.
When the user views a video in the time shift mode, the user generally wants to view a previous scene again when advertisements or uninteresting scenes are broadcast. For this purpose, if the user requests the previous scene, a reproduction is executed from the previous scene and thus a reproducing position of the video is changed.
Like this, when advertisements or uninteresting scenes are ended and new contents are started while the user is viewing the previous broadcasting, or when interesting scenes that the user wants to view are started, the user wants to switch to the new contents or the interesting scenes even in the time shift.
In case of a general time shift function, however, it is impossible to view a time shifted scene and a current broadcasting scene at the same time. Therefore, it is impossible to swiftly switch to the current broadcasting scene at a desired point of time.
In addition, when the user switches from the time shifted scene to the current broadcasting scene but wants to switch to the time shifted scene again, it is impossible to switch to the previous scene because there is no recording about position of the previous scene.
FIG. 1 is a schematic block diagram of an image recording and reproducing apparatus according to the related art.
Referring to FIG. 1, a mode setup unit 11 determines whether to record a broadcast signal. In other words, a user selects a mode about whether to record a current incoming broadcast signal using a remote controller or the like. For example, when the user selects a live mode, the broadcast signal is inputted as a live signal to a signal selecting unit 15 as it is. Then, the live signal is decoded by a decoding unit 17 and displayed on a display unit 19.
On the other hand, when the user selects a time shift mode, the broadcast signal is branched into a live signal and a time shift signal. The live signal is inputted to the signal selecting unit 15, while the time shift signal is stored in a recording/storing unit 13.
Like this, when the mode setup unit 11 sets a current mode to the time shift mode, the broadcast signal is inputted to the signal selecting unit 15 for its reproduction and stored in the recording/storing unit 13 at the same time.
Meanwhile, in case of the time shift mode, the time shift signal is stored in the recording/storing unit 13 and again inputted to the signal selecting unit 15 at the same time.
The signal selecting unit 15 selects one of the live signal and the time shift signal and transmits the selected signal to the decoding unit 17. At this time, the user can select one of the live signal and the time shift signal. In other words, if the user wants to view a live broadcasting, the live signal is selected and inputted to the decoding unit 17, and if the user wants to view a previous broadcasting, the time shift signal is selected.
Then, the decoding unit 17 decodes the selected signal.
The decoded signal is displayed on a screen of a display unit 19.
In other words, if the signal selecting unit 15 selects the live signal, the current broadcasting scene is displayed, and if the signal selecting unit 15 selects the time shift signal, the previous broadcasting scene is displayed. Here, the previous broadcasting is a stream that is recorded continuously together with the current broadcasting. Also, the previous broadcasting is a term indicating a previous portion of the current broadcasting in a stream that recorded continuously together with the current broadcasting in a state that the user requests the time shift and the time shift stop command is not issued. In other words, the previous broadcasting means a portion prior to the live position in the time shift stream, that is, a portion that is recorded before the live position and stored in a storage unit.
In case of the time shift mode, such a conventional image recording and reproducing apparatus constructed as above displays only the selected signal (that is, one of the live signal and the time shift signal) on the screen.
Accordingly, the user cannot view the current broadcasting and the previous broadcasting at the same time. In other words, in case of switching to the previous broadcasting while uninteresting scenes are displayed in the current broadcasting, the previous broadcasting alone is displayed on the screen. Therefore, the user cannot obtain any information about whether new program is started, whether the uninteresting scenes are yet displayed, or whether interesting scenes are displayed.
As a result, the user cannot view well the current broadcasting and the previous broadcasting because the user must frequently switch to the current broadcasting in order to check the status of the current broadcasting. In addition, the user continues to manipulate the remote controller in order to switch between the current broadcasting and the previous broadcasting, thereby causing the user's inconvenience.
Meanwhile, when the user switches from the previous broadcasting to the current broadcasting but wants to switch to the previous broadcasting again, it is impossible to switch to the previously stopped position because there is no recording about a reproducing end position of the previous broadcasting.